Building panels are ubiquitous in the building industry and are used to form walls, doors or other partitions, either of a structural or non-structural nature. Building panels are conventionally made from wood, most commonly plywood, wood chips or a composite material such as medium density fibreboard (MDF).
Engineered wood products, such as MDF, are made by breaking down hardwood or softwood residuals into wood fibres, and combining the fibres with wax and a resin binder. Panels are formed therefrom by applying high temperature and pressure. It is has been found that the resin material used in the manufacture of wood chip or composite-type panels is carcinogenic. Such panels are further disadvantageous in that they are relatively heavy and require additional components in order to be moisture resistant.
An alternative type of composite building panel is that produced from sand, cement and cellulose fibres, otherwise known as a fibre cement panel. Fibre cement panels are most often manufactured in a sheet form and are commonly used as cladding, but can also be used as tile underlay on decks and in bathrooms. While water and fire resistant, fibre cement panels are disadvantageous in that they are typically very heavy, where only thick panels have good impact resistance. Thin fibre cement panels are very fragile and must be handled carefully to avoid chipping and breakage.
A further alternative type of building panel is that made from moulded polyurethane. Polyurethane can be formed into panel which can function in the same manner as conventional panels formed from wood and other material. The panel is able to be cut, screwed, drilled, painted, laminated or veneered. Panels made from polyurethane avoid the use of the carcinogenic resin used in MDF panels, and are considerably lighter than similarly sized panels made from, for example, MDF, plywood or fibre cement. Polyurethane panels are also non-toxic, waterproof, flexible, and thermoformable. Polyurethane panels provide superior, cost efficient applications across many industries including, for example, marine, building and construction, landscaping, signage, transportation and refrigeration. The panels have excellent thermal and acoustic properties, and can also be made fire resistant. While laminating or veneering polyurethane panels with, for example, melamine or plywood, improves strength and rigidity, this is at a cost to flexibility and, consequently, the applicability of panels.
A need exists to provide improved polyurethane panels for use in building an other applications. The present invention addresses this need.
Discussion or mention of any piece of prior art in this specification is not to be taken as an admission that the prior art is part of the common general knowledge of the skilled addressee of the specification in Australia or any other country.